Recently, automobiles are equipped with many electric and electronic devices and microcomputers. The microcomputer controls the electric and electronic devices. The electric and electronic devices are connected by means of connection lines such as wire harnesses and flat cables. In order to facilitate the assembly of components and maintenance, the connection of the connection lines is carried out using a pair of male and female connectors that can be easily connected and removed. A variety of male and female connectors of this type are commercially available and utilized. However, a poor connection of connectors may cause a failure. Accordingly, what is proposed is a connector that allows the detection of the joined state of the connectors, specifically, an incompletely joined state that is likely to happen when connectors are being joined together, resulting in the so-called half-fitted state.
For example, JP-A-10-50408 discloses a connector-fitting construction that allows detection of a half-fitted state. In the following, referring to FIGS. 10 and 11, the connector disclosed in JP-A-10-50408 will be described. It is noted that FIG. 10 is an exploded perspective view of male and female connectors and FIG. 11 is a cross-sectional view showing the male and female connectors in a joined state.
The connector fitting construction includes a pair of male and female connectors in which a half-fitted condition is detected when those connectors are being joined together. The male connector 20 includes a predetermined number of socket contacts 21 (see FIG. 11) and a male housing 22 having terminal receiving chambers for receiving the respective socket contacts. The male housing 22 includes a connector housing 22A open to the front side and an exclusive-use housing 22B formed above the connector housing 22A. A slider 30 is slidably mounted in the exclusive-use housing 22B. Guide grooves 23 are provided at both ends of the exclusive-use housing 22B to guide both sides of the slider body. A spring-receiving portion 22C of a tubular shape is provided at each of the rear ends of the guide grooves 23. A lock-arm 24 of a cantilever type made of an elastic member is integrally formed at the middle of the exclusive-use housing 22B to extend in the fitting direction. A lock beak 25 having a slanting surface is formed on the upper surface of the lock arm 24. A housing lock 26 (engagement projection) for retaining engagement with a female housing 41 is formed on the lower surface of the lock arm 24 at the distal end thereof. Displacement prevention projections 26a for preventing displacement of the lock arm 24 are formed on that portion of the upper surface of the lock arm 24 facing away from the housing lock 26. Side spaces 27a for receiving respective abutment projections of a slider arm are provided on both sides of the lock arm 24.
An elastic slider arm 32 of the cantilever type is formed at the generally central portion of the slider body 31. The slider arm 32 has a pair of abutment projections 34 at both sides of a lower surface thereof at a front end thereof. The slider 30 further includes a press portion 35 formed on an upper surface thereof at a rear end thereof and operated when releasing the fitted condition, a slider groove 33 formed in the slider arm 32 and the press portion 35, and spring retaining portions 36 formed at both sides of the rear end thereof on the lower surface thereof to retain compression springs 38. A displacement prevention portion 37 for preventing displacement of the lock arm 24 is formed at the front end of the slider body 31.
The slider 30 is attached to the male connector 20. More specifically, with the compression springs 38 entering a slider retaining portion 27 from the front side of the male connector 20, the slider 30 is pushed into the slider receiving portion 27. At this time, the abutment projections 34 formed at both sides of the lower surface of the slider arm 32 are disposed in the respective side spaces 27a provided on both sides of the lock arm 24. The compression springs 38 are received in the respective spring receiving portions 22C, and the lock beam 25 on the lock arm 24 is fitted in the slide groove 33 of the slider 30. Thus, the slider 30 is slidably mounted. The slider 30 is urged forwardly by the resilient force of the compression springs 38. The front end of the press portion 35 is retained by the lock beak 25 received in the slide groove 33, and the displacement prevention projections 26a formed at the front end of the lock arm 24 abut against the displacement prevention portion 37 formed at the lower surface of the front end of the slider 30, so that the lock arm 24 is prevented from being displaced upward.
On the other hand, the female connector 40 includes a predetermined number of pin contacts 45 (see FIG. 11) and a female housing 41 having terminal receiving chambers for receiving the respective pin contacts. The female housing has a housing insertion hole 46 open to the front side. Formed on a surface of the housing 41 are a pair of stopper projections 42 for abutting against the abutment projections 34 of the slider 30 when fitting the connectors together. A slanting projection 43 having a slanting surface for flexing the lock arm 24 is formed between the stopper projections 42. An engagement groove 44 for engagement with the housing lock (engagement projection) 26 is formed adjacent to the rear end of the slanting projections 43.
The operation of fitting the male connector 20 and the female connector 40 together will be described. When the male connector 20 is inserted into the female connector 40, the stopper projections 42 of the female connector 40 are fitted into the respective side spaces 27a provided on both sides of the lock arm 24 of the male connector 20, and the stopper projections 42 abut against the respective abutment projections 34 of the slider 30. Upon the abutment, the resilient force of the compression springs 38 is produced. At this stage, the pin contacts 45 in the female connector 40 have not yet been inserted into the respective socket contacts 21 in the male connector 20. Then, when the male connector is further inserted, the slider 30 is pushed rearward against the bias of the compression springs 38, and the housing lock 26 at the front end of the lock arm 24 abuts against the slanting projection 43 of the female connector 40. At this stage, the pin contacts 45 are inserted into the respective socket contacts 21 but are not completely electrically connected thereto. If the pushing operation is stopped in this half-fitted condition, the female and male connectors 40 and 20 are moved away from each other in a disengaging direction (opposite to the fitting direction) by the resilient force of the compression springs 38, and therefore, the half-fitted condition can be easily detected.
Then, when the male connector is further inserted, the slider arm 32 of the slider 30 is flexed upwardly by the lock beak 25, so that abutment of the stopper projections 42 against the abutment projections 34 of the slider 30 is released. Then, the housing lock 26 at the front end of the lock arm 24 slides over the slanting projections 43 and is about to be engaged in the engagement groove 44. Because of the resilient force of the compression springs 38, the slider arm 32 slides over the stopper projections 42, and the housing lock 26 becomes engaged in the engagement groove 44. Accordingly, the slider 30 is returned to its initial position by the resilient force of the compression springs 38, and the displacement prevention portion 37 of the slider 30 abuts against the displacement prevention projections 26a of the lock arm 24, thereby locking the lock arm 24. Thus, the male and female connectors are completely fitted together, and their contacts are completely connected with each other. This completely fitted condition can be tactilely detected when the housing lock 26 of the lock arm 24 slides over the slanting projection 43, and also can be easily detected by visually confirming the position of the returned slider 30.
With the connector disclosed in JP-A-10-50408, the half-fitted condition can be detected tactilely when the housing lock of the lock arm slides over the slanting projection when the connectors are being jointed together or by visually confirming the moved position of the slider. However, connectors of this kind, including the connector as described above, are joined in a freely moving state in which the male housing of the male connector and the female housing of the female connector are not firmly joined but rather with a slight gap G (see FIG. 11) formed between the housings even when the connectors are completely fitted after the half-fitted state is detected at a time of fitting together. Such joining in a freely moving state causes the connectors to be displaced in the fitting direction, that is, the longitudinal direction of connection when the connectors are exposed to vibrations. The displacement, which is called rattling, may cause poor contact between the socket contact and the pin contact of the female and male connectors. In particular, if the connectors of this kind are used in vehicles such as automobiles where they are frequently exposed to vibrations, poor contact occurs and may result in a failure. An improvement is thus required.